Jay Cutler passed to Brandon Marshall for the go-ahead touchdown in the fourth quarter, helping the Bears rally for a 24-21 victory over the sloppy Cincinnati Bengals on Sunday and giving Trestman a victory in his first game as an NFL head coach.

It wasn't quite the display the Bears were looking for after making some big changes in the offseason. But they made the most of a handful of big plays by Cutler and repeated mistakes by the Bengals.

"There were a lot of question marks," Cutler said. "How were we going to do on offense? Are the plays going to work? Are we going to be able to block them? Am I going to complete balls? So to go out there, it wasn't pretty, it wasn't perfect, we didn't think it was going to be. We made plays when we had to make plays."

Cutler threw for 242 yards behind a line with four new starters. Marshall had eight grabs for 104 yards, and the offense pulled it out after struggling most of the way.

The Bengals led by 11 in the third quarter and were up 21-17 early in the fourth when Tim Jennings jarred the ball from Mohamed Sanu following a reception and made the recovery.

Chicago took over at its 19 and got an 8-yard run from Matt Forte on fourth-and-inches at the Bengals 27 to keep the drive going. Cutler then found Marshall in the front corner of the end zone for a 19-yard touchdown with 7:58 remaining.

The Bears made big changes in the offseason, parting with star linebacker Brian Urlacher and hiring Trestman to replace the fired Lovie Smith with the idea that he could spark the offense and lead them to the playoffs after missing out five of the past six years.

Clearly, there's work to do. The offense seemed stuck most of the afternoon but came through in the end, with Cutler completing 21 of 33 passes. He also had two touchdowns to go with an interception.

Charles Tillman matched a career high with two interceptions, giving him 35 overall for Chicago. And Robbie Gould set a franchise record with a 58-yard field goal at the end of the first half following some questionable clock management by Cincinnati.

"I think it tested us and our backbone because it didn't go the way we wanted it to go, certainly, in the first half," said Trestman, who coached the CFL's Montreal Alouettes the past five seasons. "But the guys hung in there together, at halftime pulled themselves together and the team went out and played every play and were able to come out on top."

Cincinnati's Andy Dalton threw for 282 yards with two touchdowns and two interceptions. A.J. Green had 162 yards receiving and two touchdowns, including a 45-yarder. But it was a disappointing opener for a team coming off back-to-back playoff appearances for the first time since 1981 and 1982.

"They didn't stop us one time," Green said. "They didn't really stop us on offense. We were doing whatever we wanted. The biggest thing we had was turnovers."

Up 14-10 at the half, the Bengals started the third quarter with an 80-yard scoring drive.

Tillman got called for interference on a deep pass to Green that put the ball on the 1, and BenJarvus Green-Ellis plowed in from the 5 after being hit with a 4-yard loss, making it 21-10.

But the Bears responded with an 80-yard drive that ended with Forte running it in from the 1 to get them back within four.

Vontaze Burfict intercepted Cutler near midfield early in the fourth quarter, taking a shot to the right knee from Chicago's Kyle Adams.

Cincinnati took over at the Bears 40, but Sanu's fumble at the 17 led to a big swing.

And Marshall couldn't believe he was one on one with Reggie Nelson on the go-ahead touchdown.

"I didn't understand it. You know?" Marshall said. "Fourth quarter, put a safety on me one on one? You can only ask for that and dream about that."

The Bengals would have had one last chance to win or tie it, but Rey Maualuga committed a personal foul away from the play when Cincinnati stopped Michael Bush after a short gain on third-and-6 at the Cincinnati 45 with a little over a minute left.

The unnecessary roughness penalty that kept the drive going and allowed Cutler to take a knee twice, ending the game.

NOTES: Burfict said his knee was bruised. ... Green hurt a finger at one point, but Lewis said he's fine. ... Bengals LT Andrew Whitworth, recovering from offseason surgery on his left knee, was inactive. ... Gould held the previous Bears record with a 57-yard field goal against Denver on Dec. 11, 2011. ... Trestman joined Hall of Famer George Halas (1920), Neill Armstrong (1978) and Dick Jauron (1999) as the only coaches to win their Bears debut.